Python glossary

Python glossary#

argument
A value supplied when calling a function: round(3.1415, 2) has two arguments.

attribute
Information accessed on an object without calling it, such as array.shape.

class
A definition of a kind of object and the behaviour associated with it. Path and DataFrame are classes.

dictionary
A mutable collection mapping unique keys to values.

function
A named, reusable unit of behaviour that may accept inputs and return an output.

immutable
Unable to change after creation. Strings, numbers, and tuples are immutable.

instance
One concrete object created from a class: Path("data") creates a Path instance.

iterable
An object that can be visited one item at a time in a loop, such as a list, string, or file.

method
A function accessed through an object or class, such as text.lower() or model.fit().

mutable
Able to change in place. Lists, dictionaries, NumPy arrays, and DataFrames are mutable.

parameter
A name in a function definition. In def mean(values):, values is a parameter.

return value
The object produced by a function call. A function without an explicit return returns None.

array
A multidimensional collection of values, normally of one data type, represented by NumPy.

axis
One dimension of an array. Its scientific meaning depends on the dataset.

broadcasting
NumPy’s rules for applying operations to arrays with compatible but different shapes.

DataFrame
A labelled, two-dimensional pandas table with rows and columns.

estimator
A model-like object following methods such as .fit() and .predict() or .transform().

feature
An input variable supplied to a model. A feature matrix is commonly named X.

shape
A tuple describing the size of every array dimension, for example (80, 32, 500).

tensor
A general term for a multidimensional numeric array, particularly common in deep learning.

dependency
A package required by a project.

interpreter
The Python program that executes code. Different environments can contain different interpreters.

module
A Python file that can define functions, classes, and variables for import.

package
An installable collection of Python modules.

virtual environment
An isolated Python installation and package set associated with a project.

working directory
The directory from which relative paths are interpreted at runtime.